Title:
ELASTIC WAVE DEVICE
Document Type and Number:
WIPO Patent Application WO/2024/043300
Kind Code:
A1
Abstract:
Provided is an elastic wave device that makes it possible to facilitate downsizing of a filtering apparatus and to suppress degradation of filtering characteristics. An elastic wave device 10 according to the present invention is provided with: a first elastic wave resonator 10A that has a first piezoelectric film including a first piezoelectric layer (piezoelectric layer 14) comprising a piezoelectric material; and at least one second elastic wave resonator 10B that is electrically connected to the first elastic wave resonator 10A and that has a second piezoelectric film including a second piezoelectric layer (piezoelectric layer 14) comprising a piezoelectric material and an IDT electrode 31 provided on the second piezoelectric layer. The first elastic wave resonator 10A includes: a first comb-shaped electrode that is provided on the first piezoelectric layer, that has a first bus bar and a plurality of first electrode fingers 25 having one ends connected to the first bus bar, and that is connected to an input potential; a second comb-shaped electrode that is provided on the first piezoelectric layer, that has a second bus bar and a plurality of second electrode fingers 26 having one ends connected to the second bus bar and being interpolated in the plurality of first electrode fingers 25, and that is connected to an output potential; and a third electrode that has a plurality of third electrode fingers 27 provided on the first piezoelectric layer so as to be arrayed, in a plan view, side by side with the first electrode fingers 25 and the second electrode fingers 26 in a direction in which the first electrode fingers 25 and the second electrode fingers 26 are arrayed, and has a connection electrode (third bus bar 24) for connecting the adjoining third electrode fingers 27, and that is connected to a potential different from those for the first comb-shaped electrode and the second comb-shaped electrode. Regarding the order of the array of the first electrode fingers 25, the second electrode fingers 26, and the third electrode fingers 27, when the array starts with the first electrode fingers 25, the order of the first electrode fingers 25, the third electrode fingers 27, the second electrode fingers 26, and the third electrode fingers 27 forms one cycle. The IDT electrode 31 of the second elastic wave resonator 10B has a plurality of fourth electrode fingers 35 and a plurality of fifth electrode fingers 36 which are mutually interpolated. The second elastic wave resonator 10B is a series-arm resonator or a parallel-arm resonator.
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Inventors:
NAGATOMO SHO (JP)
DAIMON KATSUYA (JP)
DAIMON KATSUYA (JP)
Application Number:
PCT/JP2023/030459
Publication Date:
February 29, 2024
Filing Date:
August 24, 2023
Export Citation:
Assignee:
MURATA MANUFACTURING CO (JP)
International Classes:
H03H9/145; H03H9/64
Domestic Patent References:
| WO2022163865A1 | 2022-08-04 |
Foreign References:
| JPH11186867A | 1999-07-09 | |||
| JPH0774582A | 1995-03-17 | |||
| JP2022067077A | 2022-05-02 |
Attorney, Agent or Firm:
OSAKA FRONT (JP)
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